Because it relates to more than one branch of knowledge. It combines more than one academic disiplines.
Hey there!
27 tells us the sum of protons and neutrons is 27.
Al tells us we have 13 protons.
3+ tells us that there are 3 less electrons than protons.
13 + n = 27
neutrons = 14
13 - 3 = 10 electrons
27Al3+ has 13 protons, 14 neutrons, and 10 electrons.
Hope this helps!
Answer:
The United States leads the world with over 260 billion short tons of recoverable coal reserves—28% of total global reserves and 50% more than Russia, which possesses the world's second largest reserves. so the answer would be 28%
Explanation: